Stop motion mechanism for sewing machines



y 1965 s. J. KETTERER ETAL 3,196,816

STOP MOTION MECHANISM FOR SEWING MACHINES 4 Sheets-Sheet 1 Filed Aug. 7, 1965 1 III llll INVENTORS. 2 STANLEY J. KETTERER,

ROBERT W. BUSCH, JR. and BY MICHAEL F. IVANKO M43710 E WITNESS July 27, E965 s. .n. KETTERER ETAL STOP MOTION MECHANISM FOR SEWING MACHINES 4 Sheets-$heet 2 Filed Aug. 7, 1963 IR R- mE v! 0 mmun'K W T N R NTMWA 0 Err- V T W 9 J rr Y Lu R ENE MEM/ mwm SRM Y 7, 1965 s. J. KETTERER ETAIL. 3,l96,

STOP MOTION MECHANISM FOR SEWING MACHINES 4 Sheets-Sheet 3 Filed Aug. 7, 1963 Ill III I llllr lllll\lllll I STANLEY J KETTERER, ROBERT W. BUSCH, JR. and MICHAEL F. IVAN 0 Y 1965 5. J. KETTERER ETAL 3,196,81

STOP MOTION MECHANISM FOR SEWING MACHINES Filed Aug. '7, 1963 4 Sheets-Sheet 4 INVENTORS. STANLEY J. K E TTERER, ROBERT W BUSCH, JR. and MICHAEL F. IVANKO WITNESS United States Patent 3,1%,816 T0? MUTIQN MECHANISM FOR SEWING MACHINES tanley .l. lifietterer, Morris Plains, Robert W. Busch, lira,

Eoonton, and Michael F. Ivanko, Roekaway, N.J., assignors to The Singer Company, New York, N.Y., a corporation of New Jersey Filed Aug. 7, 1563, Ser. No. 3%,562 6 Claims. (Cl. 1l2-219) This invention relates to sewing machine driving devices, and more particularly to a novel and improved stop motion mechanism for a cyclically operated sewing machine.

It is an object of this invention to provide a belt driven sewing machine stop motion mechanism including a planetary gear system for driving the sewing machine through an intermediate low speed as it is being stopped and in which the planetary gear system remains completely immobilized while the sewing machine is stopped.

Another object of this invention is to provide in a planetary controlled stop motion device a novel cushioning arrangement for damping the shock incident to abrupt stopping of the sewing machine.

With the above and additional objects and advantages in View as will hereinafter appear, this invention comprises the devices, combinations and arrangements of parts hereinafter described and illustrated in the accompanying drawings of a preferred embodiment in which:

FIG. 1 represents a rear elevational view of a sewing machine having the stop motion device of this invention applied thereto,

FIG. 2 represents a bottom plan view of a portion of the control cams of the sewing machine of FIG. I viewed substantially along line 2-2 of FIG. 1,

FIG. 3 represents a left side elevational view of a portion of the sewing machine of FIG. 1 with the pulley and planetary gear assembly of this invention illustrated in vertical cross section taken substantially along line 3-3 of FIG. 1 and with the stop motion mechanism illustrated in solid lines in position corresponding to the stopped condition of the sewing machine,

FIG. 4 represents a right side elevational view of a portion of the sewing machine of FIG. 1 with the stop motion mechanism illustrated in position corresponding to the stopped condition of the sewing machine,

FIG. 5 represents a right side elevational view of a portion of the sewing machine of FIG. 1 with the stop motion mechanism illustrated in position corresponding to the high speed running condition of the sewing machine,

FIG. 6 represents a right side elevational view of a portion of the sewing machine of FIG. 1 with the stop motion mechanism illustrated in position corr sponding to the transitory low speed running conditions of the sewing machine, and,

FIG. 7 represents an exploded perspective view of the pulley and planetary gear assembly of this invention.

Referring to the drawings, this invention is illustrated as applied to a sewing machine of the type described in detail in United States Patent No. 2,938,477, May 31, 1960 of M. Ivanko and R. P. Graham. The sewing machine frame includes a base 11 upon which is secured a bracket arm 12. Co-operating stitch forming mechanism (not shown) on the base and bracket arm are actuated from a main shaft 13 journaled in the bracket arm. The base 11 is secured on a sub-base 14 in which is journaled a pattern cam 15 with a driven gear 16 attached thereto. Meshing with the gear 16 is a pinion 17 on a shaft 1% extending upwardly through the base and carrying a worm wheel 19 in mesh with a worm Ztl on the main shaft l3.

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The sewing machine is of a group stitch or cyclic variety. Each cycle of operation commences at the will of the operator, continues for one rotation of the pattern cam 15, and terminates in response to signals from a pair of cam lugs 21 and 22 secured by fastening screws 23 and 24, respectively, beneath the pattern cam 15. The cam lugs 21 and 22 influence in seriatim a follower arm 25 fixed to a rock shaft 26 journaled vertically alongside the machine frame base 11 which serves in co-operation with the stop motion mechanism of this invention as will be described hereinbelow to stop the sewing machine in a predetermined position of the parts.

The sewing machine may have associated therewith various conventional ancillary devices such as thread trimmers, work clamp or presser lif ers, etc. cillary devices are not illustrated in the drawings since they may be of any conventional construction, however, there is illustrated in the drawings a slide bar 27 sup ported for lengthwise sliding movement at the juncture of the base 11 and the bracket arm 12 of the frame. The slide bar 27 may be used to operate, for instance, a thread trimming device. Also illustrated with drawings is a rock shaft 23 journaled in the bracket arm 12 which may be connected, for instance, to a work clamp lifting linkage. The above referenced United States Patent No. 2,938,477 describes such ancillary devices in detail and may be referred to for a description thereof.

The slide bar 27 and rock shaft 28 may be operated by a lever 3i) fulcrumed on a stud 31 set into the bracket arm 12. A link 32 connects the lever 3% with a rock arm 33 on a rock shaft 28, while a link 34 pivotally connects the lever with a bifurcated lever 35 which is fulcrumed at 36 in the bracket arm 12 and embraces a slide block 37 carried on the slide bar 27. An operator influenced lever 38 is also fulcrumed on the stud 31 and has pivoted thereto a pawl 39 which is biased by a leaf spring 40 into engagement with a pawl seat 41 formed in the lever (iii. A control arm 42 on the pawl serves as will be described hereinbelow to shift the pawl 39 against the action of the spring 40 and out of the pawl seat 41 to prevent manual operation of the slide bar 27 and rock shaft 28 at inopportune times during a stitching cycle.

The slide bar 27 is also operatively connected to a rock arm 43 fast on a sleeve 44 on the rock shaft 26. As illustrated in FIGS. 1 and 2 a rock arm 45 on the sleeve 44 is connected by a link 46 to a cam follower lever 47 carrying a cam follower roller 48 tracking a cam groove 45 in the underside of the pattern cam 15. The pattern cam 15 can thus influence operation of the auxiliary devices controlled by the slide bar 27 and furthermore, an opening 59 from the cam groove 49 to the outside of the pattern cam 15 can free the slide bar 27 for manual operation in one selected position of the sewing machine parts, as for instance, only in the predetermined stop position of the parts.

The stop motion device of this invention comprises a pulley unit indicated generally at 60 in FIGS. 1, 3, 4, 5, and 6, carried on the main shaft 13, and a belt shifting and control unit indicated generally at 61 in FIGS. 1, 3, 4, 5, and 6, carried on a support bracket 62 secured exteriorly of the bracket arm 12 by the fulcrum stud 31, a corresponding fastening stud 63 at the opposite side of the bracket 62, and by locating screws 64 threaded in the bracket 62- and bearing against the sewing machine bracket arm 12.

The stop motion of this invention may then be manufactured conveniently in two sub-assemblies 6i) and 61; it may be applied, adjusted or repaired readily since it is carried completely exteriorly of the machine frame; and it is readily adapted for application to machines originally Such andesigned for other less effective types of stop motion mechanisms.

Referring particularly to FIGS. 3 and 7, the pulley unit of the stop motion mechanism of this invention comprises a flanged collar formed with a main shaft accommodating bore 71 provided with a keyway 72 which cooperates with a keyway formed with main shaft to accommodate a key 73 locking the collar 72 fast on the main shaft 13.

The flanged collar 70 includes a threaded hub 74 on which is fitted a companion flanged collar 75 which is secured to the collar 70 by a nut 7 6 on the threaded hub 74- and by aset screw 77. The contiguous faces of the flanged collars 70 and 75 are formed with similar annular ribs 78 each of the ribs being formed with spaced notches 79.

Clamped between the collars 70 and 75 is the inner portion of a torus shaped flexible cushioning member 80 preferably formed as a molded unit and including at each side an annular groove 81 with spaced projections 82 corresponding and mating with the notched ribs 78 on the collars 70 and 75 so that the cushioning member 80 will be interengaged with as well as tightly compressed between the flanged oollars 70 and 75.

The cushioning member 30 projects radially beyond the collars 70 and 75 and is formed at each side with a second set of annular grooves 83 with spaced projections 84. The annular groove-s 83 in the cushioning member 80 accommodate like annular ribs 85 formed on the contiguous faces of a pair of rings 86, 87, which are clamped one at each side of the cushioning member 80 by a series of fastening screws 88 threaded into a keeper ring 89. The ribs 85 are formed with spaced notches 90 accommodating the projections 84 of the annular grooves 83 so that the cushioning member will be interengaged with as well as tightly compressed between the rings 86 and 87.

The ring 87 is formed with an outer cylindrical flange 91 overlying the outer periphery of the cushioning member 80. Both the flange 91 of the ring 87 and the ring 36 are formed with notched seats 92, 93, respectively, which seats are arranged in alignment when the parts are assembled so as to provide a stop notch for arresting the sewing machine in a predetermined stopped position of parts.

Fixed in the flanged collar 70 and extending laterally therefrom are three evenly spaced studs 100. Journaled one on each of the studs are three hushed planet gears 101. Encircling the planet gears i a pulley sheave ring 102 formed with internal gear teeth 103 meshing with each of the planet gears 101. Meshing with each of the planet gear 101 is a sun gear 104 fast on a pulley sheave disk 105 journaled by means of needle bearings 11% on the main shaft. Journaled freely on the main shaft 13 on needle bearings 107 adjacent to the pulley sheave disk 105 is an idler pulley 108 formed with an edge flange 103 and constrained on the main shaft by a spring clip 11A.

Referring now to the belt shifting and stop motion control unit 61, an operator-influenced lever at one side of the bracket 62 is fast on a stud shaft 121 journaled transversely through the bracket 62 of the control unit. At the opposite side of the bracket 62 from the lever 129, a rocking plate 122 together with a cam member 123 is secured to the stud shaft 121 by a split clamp 124 and a clamp screw 125. The operator-influenced lever 120 is biased toward an at rest position as illustrated in FIGS. 3 and 4 by a spring 126 and is formed with an aperture 127 of which at least one side wall 128 provides a cam surface which works against a follower pin 129 extending outwardly through an elongate slot 130 in the bracket 62 from a stop block 131 slidable lengthwise in a vertical channel 132 formed in the bracket 62. The stop block 131 is biased upwardly by a spring 133 on a bore 134 in alignment with the channel 132 into a position in which the upper extremity of the stop block will enter the 4t notched seat 92-93 so as to arrest the main shaft 13 in a predetermined stopped position. On depression of the lever 120, the cam surface 128 will shift the stop block downwardly out of the notched seat 92-93 thus freeing the main shaft for rotation.

The slide block 131 along one side is formed with an elongate slot 135 which does not extend to the free extremity of the slide block but which may be slabbed as by a transverse slot 136 to provide a camming lip 137 on the slide block 131. Extending into the slot 135 is a pin 138 formed on a collar 135 clamped on a slide rod 140 carried for endwise movement in a vertical bore 141 formed in the bracket 62. A spring 142 in the bore braces the slide rod upwardly and the upper extremity of the slide rod 140 is seated in a socket 143 formed in a brake shoe 144 which may have frictioning material 145 applied thereto and which is disposed radially beneath the pulley sheave ring 102. The camming lip 137 on the slide block 131 is preferably arranged relatively to the pin 138 so that the slide block must move completely out of the stop notch 9293 before the brake shoe 144 will be lowered out of engagement with the sheave 102.

Referring to FIGS. 4, 5, and 6, a belt shifting arm is pivoted to the bracket 62 at 151 and carries a spaced pair of rollers 152 which straddle a belt 153 which rides on the pulley sheaves 1412, 165, 108 and may be connected to any desired source of power such as an electric motor or the like (not shown).

The belt shifting arm 150 is formed with a cam slot 154 entered by a stud 155 fast on the rocking plate 122. The stud 155 is preferably arranged on the plate 122 in such position that when the operator-influenced lever 120 is biased to an extreme position by the spring 126, the belt 153 will ride completely on the idler pulley 108 as illustrated in FIG. 4; as the lever 120 is depressed to an intermediate position, shown in FIG. 5, the belt will be shifted onto the pulley sheave 105; and when the lever 120 is fully depressed, the belt 153 will ride equally in engagement with both pulley sheaves 102 and 105.

The rocking plate 122 is formed adjacent to the stud 155 with an aperture 156 formed on one edge with a pair of ratchet teeth 157 and 158 which co-operate with a pawl finger 159 clamped on the rock shaft 26. The rock shaft 26 is biased by a spring 160 to urge the pawl finger toward the ratchet teeth 157 and 158 to restrain the belt shifter into intermediate or extreme position as illustrated in FIGS. 5 and 6, respectively, until the cam lugs 21 and 22 shift the rock shaft in successive increments to release the belt shifter for return to the position illustrated in FIG. 4. A handle extension 161 on the pawl finger 159 provides for operator-influenced release of the stop motion mechanism.

As illustrated in FIGS. 4, 5, and 6, the cam member 123 fast with the rocking plate 122 will engage and shift the control arm 42 of the pawl 39 to disconnect the levers 30 and 38 in all positions of the rocking plate 122 except that in which it is completely released as illustrated in FIG. 4. It will be impossible, therefore, manually to operate any appurtenance to the sewing machine controlled by the slide rod 27 or the rock shaft 28 except while the stop motion mechanism occupies idling position, and if such an appurtenance is being manually operated it will be automatically released if the stop motion niechanism is shifted out of idling position.

Operations While the sewing machine is at rest and the stop motion parts occupy the positions illustrated in FIGS. 3 and 4, the stop block 131 will be biased into the stop notch 92- 93 locking the sewing machine main shaft in predetermined stopped position, and the brake shoe 144 will be braced against the pulley sheave 102. As illustrated in FIG. 4, the belt shifter arm 150 will have positioned the belt 153 on the idler pulley 108 so that both pulley sheaves 102 and 105 will remain at rest as will the planetary gearing 101, 103, and 104. The cam member 123 will be shifted out of engagement with the control arm 42 of the pawl 39 so that appurtenances to the sewing machine operated by slide bar 27 or rock shaft 28 may be influenced by manual operation of the lever 38.

When the lever 120 is depressed, the parts just assume the intermediate position illustrated in FIG. 6. The cam member 123 depresses the control arm 42 releasing the pawl 39 from the seat 41 and separating the levers 30 and 33 so that manual operation of appurtenances by way of the slide bar 27 and rock arm 28 are no longer possible. The cam surface 128 on the lever 120 will depress the follower 129 withdrawing the stop notch 131 from the stop notch 92-93, thus freeing the sewing machine main shaft for rotation. The brake shoe 144, however, will remain in engagement with the pulley sheave 102. The belt shifter 150 will move the belt 153 into a position in engagement with the pulley sheave 105. The pawl finger 159 by engaging the ratchet tooth 157 will retain the lever 120 and prevent retrogression. The belt will thus drive the sun gear 104, and with the ring gear 103 remaining stationary because of the brake shoe 144, the main shaft wiil be driven at a reduced speed which is a function of the sizes of the gears 101, 103, and 104. The initial acceleration of the sewing machine will, therefore, be smooth and gradual.

Further depression of the lever 120 will shift the parts into full running position as illustrated in FIG. 5 in which the belt shifter 150 will carry the belt 153 into a position spanning both pulley sheaves 102, 105, and thus locking the sheaves 102 and 105 for rotation together at the peripheral speed of the belt 153. The pawl finger 159 will engage the ratchet tooth 158 to retain the control mechanism 61 in the position illustrated in FIG. 5. The cam surface 128 on the lever 120 will shift the stop block downwardly and carry the camming lip 137 thereon into engagement with the pin 138 so as to draw the brake shoe 144 away from the pulley sheave 102. The belt 153 in engaging both pulley sheaves 102 and 105 will lock the planetary gear system 101, 103, and 104, for rotation as a unit and the sewing machine mainshaft 13 will be operated at high speed.

Machine operation at high speed will continue until the cam lug 21 on the pattern cam shifts the follower 25 so as to release the pawl finger 159 from the ratchet tooth 158 to the ratchet tooth 157 as illustrated in FIG. 6. The belt 153 will then be shifted to the pulley sheave 105 and the brake shoe will be applied to the pulley sheave 102. The planetary drive system 101, 103, and 104 will thus be rendered operative and will become effective as soon as the inertia from the sewing machine main shaft can be assumed by the belt 153 and the brake shoe 144.

Either during high speed operations or during the period while the sewing machine is assuming an intermediate speed prior to stopping, the cam groove 49 may be formed to act upon the follower 48 to shift an appurtenance to the sewing machine at a specific time during the sewing cycle. The cam groove 49 may be used, for instance, to cause a thread trimming mechanism to seize thread loops during the last stitch of a sewing cycle.

After a predetermined interval and preferably when the sewing machine has assumed the intermediate speed of operation provided by the planetary gear system 101, 103 and 104, which interval may be selected by way of the fastenings 23, 24, the cam lug 22 will trip the follower 25 to shift the pawl finger 159 out of engagement with the ratchet tooth 158.

The belt 153 will then be shifted to the idler pulley 108 as illustrated in FIGS. 3 and 4 and the cam surface 128 on the lever 120 will release the stop block 131 to bear against the outer periphery of the rings 86 and 87 clamped on the cushioning member 80. The stop block will then enter the seat 92-03 when the main shaft 13 next assumes a predetermined position of rotation and the main shaft will be locked in stopped position. Having progressed through an intermediate low speed, the inertia of the sewing machine parts will have been considerably reduced and the remaining inertia will be absorbed by the cushioning member 80.

In the stopped position of the parts as illustrated in FIGS. 3 and 4 the cam member 123 will have been shifted free of the control arm 42 of the pawl 39 and the levers 30 and 38 will be re-established in operative connection. Similarly the cam follower 48 will occupy a position opposite the opening 50 in the cam groove 49 so that the slide rod 27 and the rock shaft 28 may be operated manually.

Having set forth thenature of this invention that we claim herein is:

1. A stop motion mechanism for a cyclic sewing machine having a frame, a main drive shaft operatively connected to stitch forming mechanism in said frame, and a cam member drivingly connected with said main drive shaft, said stop motion mechanism comprising a planetary gear system carried on said main drive shaft and including a plurality of planet gears, means for journaling said planet gears on parallel axes secured for rotation with said main drive shaft, a pulley ring embracing said planet gears and formed with internal gear teeth meshing with said planet gears, a sun gear meshing with said planet gears and secured to a pulley of equal diameter and adjacent to said pulley ring, and an idler pulley of equal diameter and adjacent to said sun gear pulley, a control unit carried by said sewing machine frame and including a belt shifter effective to sustain a belt in one of three positions; a first position engaging said idler pulley, a second position engaging said sun gear pulley and a third position engaging both said sun gear pulley and said pulley ring, a brake shoe on said control unit engageable with said pulley ring, means associated with said belt shifter for carrying said brake shoe out of engagement with said pulley ring while said belt shifter occupies said third position, positive interengaging stop means carried on said control unit and on said main drive shaft, means associated with said belt shifter for rendering said interengaging stop means ineffective while said belt shifter occupies said second and said third positions, operator influenced means for moving said belt shifter in seriatim from said first to said third position, said means influenced by said sewing machine cam means for influencing movement of said belt shifter in seriatim from said third to said first positions.

2. A stop motion mechanism as set forth in claim 1 in which said control unit includes a lever operatively connected to said belt shifter and in which said means for carrying said brake shoe out of engagement with said pulley ring and said means for rendering said interengaging stop means ineffective comprises a single cam surface formed in said lever.

3. A stop motion mechanism as set forth in claim 1 for a sewing machine having an appurtenance actuated by an operator influenced linkage, means operatively connecting said belt shifter and said operator influenced linkage to render said operator influenced linkage effective only in said first portion of said belt shifter.

4. A stop motion mechanism as set forth in claim 1 in which said interengaging stop means comprises a stop finger carried by said control unit and a torus shaped flexible cushioning member, means for clamping an inner portion of said flexible cushioning member on said main shaft, a ring formed with a stop finger accommodating notch, and means for clamping said ring on an outer portion of said flexible cushioning member.

5. A stop motion mechanism as set forth in claim 4 in which said means for clamping said flexible cushioning member on said main shaft comprises spaced flanges on said main shaft each having an annular rib formed with spaced notches, fastening means for compressing said flexible cushioning member between said spaced flanges, and said flexible cushioning member being formed with annular groove segments accommodating said annular flange ribs between said spaced notches in said annular ribs.

6. A stop motion mechanism as set forth in claim 4 in which both said means for clamping said flexible member to said main shaft and said means for clamping said ring to said flexible member includes spaced flanges carried on said main shaft and on said ring respectively, means for compressing said flexible cushioning member between said spaced flanges, said flanges and said cushioning member being formed with mating notches and projections adapted to provide a resilient interlock therebetween.

References Cited by the Examiner UNITED STATES PATENTS Mace 112220 Carr 74-785 Peets 112-220 Rockwell 74-785 Ketterer et al 112--219 Hayes 112---220 X Zeier 112-219 JORDAN FRANKLIN, Primary Examiner.

ROBERT V. SLOAN, Examiner. 

1. A STOP MOTION MECHANISM FOR A CYCLE SEWING MACHING HAVING A FRAME, A MAN DRIVE SHAFT OPERATIVELY CONNECTED TO STICH FORMING A MECHANISM IN SAID FRAME, AND A CAM MEMBER DRIVINGLY CONNECTED WITH SAID MAN DRIVE SHAFT, SAID STOP MOTION MECHANISM COMPRISING A PLANETARY GEAR SYSTEM CARRIED ON SAID MAIN DRIVE SHAFT AND INCLUDING A PLURALITY OF PALNET GEARS, MEANS FOR JOURNALING SAID PLANET GEARS ON PARALLEL AXES SECURED FOR ROTATION WITH SAID MAIN DRIVE SHAFT, A PULLEY RING EMBRACING SAID PLANET GEARS AND FORMED WIH INTERNAL GEAR TEETH MESHING WITH SAID PLANET GEARS, A SUN GEAR MESHING WITH SAID PLANET GEARD AND SECURED TO A PULLEY OF EQUAL DIAMETER AND ADJACENT TO SAID PULLEY RING, AND AN IDLER PULLEY OF EQUAL DIAMETER AND ADJACENT TO SAID SUN GEAR PULLEY, A CONTROL UNIT CARRIED BY SAID SEWING MACHINE FRAME AND INCLUDING A BELT SHIFTER EFFECTIVE TO SUBSTAIN A BELT IN ONE OF THREE POSITIONS; A FIRST POSITION ENGAGING SAID IDLER PULLEY, A SECOND POSITION ENGAGING SAID SUN GEAR PULLEY AND A THIRD POSITION ENGAGING BOTH SAID SUN GEAR PULLEY AND SAID PULLEY RING, A BRAKE SHOE ON SAID CONTROL UNIT INGAGEABLE WITH SAID PULLEY RING, MEANS 